package com.pay.util;

import java.security.MessageDigest;
import java.util.Arrays;

/**
 * Created by Administrator on 2016/6/3.
 */
public class CheckUtil {
    private static final String token = "hpj";
    private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5', '6', '7',
            '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
    public static boolean checkSignature(String signature,String timestamp,String nonce){
        String[] arr = new String[]{token,timestamp,nonce};
        //
        Arrays.sort(arr);
        StringBuffer content = new StringBuffer();
        for(int i=0; i<arr.length; i++){
            content.append(arr[i]);
        }
        String temp = encode(content.toString());
        System.out.print("\ntemp:"+temp+"\nsign:"+signature);
        return temp.equals(signature);
    }

    private static String getFormattedText(byte[] bytes) {
        int len = bytes.length;
        StringBuilder buf = new StringBuilder(len * 2);
        // 把密文转换成十六进制的字符串形式
        for (int j = 0; j < len; j++) {
            buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
            buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
        }
        return buf.toString();
    }

    public static String encode(String str) {
        if (str == null) {
            return null;
        }
        try {
            MessageDigest messageDigest = MessageDigest.getInstance("SHA1");
            messageDigest.update(str.getBytes());
            return getFormattedText(messageDigest.digest());
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
